Yukon Gear High Performance Gear Set For Dana 30 JK Short Reverse Pinion / 4.56
Most JK owners who search for 4.56 gears are in the same spot: the Jeep now sits on 33 or 35 inch tires, sixth gear is useless on the highway, and the front axle needs to be regeared to match a new rear. The Yukon Gear & Axle YG D30SR-456JK is the 4.56 ring and pinion for the Dana 30 front axle used under non-Rubicon Wrangler JK and JK Unlimited models. Per Yukon, it fits the reverse-rotation Dana 30 in the JK and has a 7.33 in. ring gear, a 24-spline short pinion and 10 ring gear bolts.
The front ring and pinion turns driveshaft speed into wheel torque, and in four-wheel drive it has to do that at exactly the same ratio as the rear axle or the two ends of the Jeep fight each other through the transfer case. The JK Dana 30 is a high-pinion, reverse-cut axle, so it needs gears made for reverse rotation; standard-rotation Dana 30 sets from a TJ, YJ or XJ will not mesh correctly. 4.56 sits in the middle of the regear range. It is about 22 percent lower than a stock 3.73 set and about 42 percent lower than 3.21, which brings engine speed back up into the useful part of the power band once taller, heavier tires are installed. Compared with 4.88, it keeps highway cruise rpm a little lower, so it is a popular middle ground for daily-driven JKs that also see trail time. Pair it with a 4.56 rear such as the Yukon JK Dana 44 rear 4.56 set or the Revolution JK Dana 44 rear 4.56 set.
Axle: this set is only for the Dana 30 front on non-Rubicon models; Rubicons have a Dana 44 front. Ratio: front and rear must match to the hundredth, so decide on 4.56 for both axles before ordering. Our regear after bigger tires guide walks through the tire-size math, and the JK regear kit buyer's guide lists everything both axles need. Carrier: the JK Dana 30 carrier break falls between 3.54 and 3.73, so a Jeep that came with 3.21 gears needs a new 3.73-and-up JK Dana 30 carrier or a locker for that series. Factory 3.73 carriers accept this ring gear.
Yukon catalogs YG D30SR-456JK for the reverse-rotation Dana 30 front on the 2007-2018 Jeep Wrangler JK and JK Unlimited without the Rubicon package, the same axle found on X, Sport, Sport S, Sahara and Anniversary models. It is not for the JK Rubicon Dana 44, the TJ or YJ Dana 30, or the 2018-and-later JL front axle. If your Jeep has had an axle swap, read the housing tag or send us the year, trim and VIN and we will check it. Running 33s and want a little less rpm? Compare the 4.11 JK front set. Browse more axle parts in our hard parts category.
Fit new bearings with new gears every time. The Spicer 10040478 JK Dana 30 master overhaul kit covers the bearings, races, shims and seals for this axle. Mark the bearing caps before removal so they go back on the same side. Set pinion depth, then preload, then backlash, and confirm the pattern with marking compound before final torque. The inner axle seal installer helps seat the tube seals squarely when the shafts go back in. Fill with the front axle gear oil specified in your owner's manual, drive gently for the first few hundred miles with no towing or wheeling, then change the oil. Our break-in procedure explains why heat control matters on fresh gears. Last step: reprogram the tire size and axle ratio so the speedometer and shift points read correctly.
| Brand | Yukon Gear & Axle |
| Part number | YG D30SR-456JK |
| Fits | Yukon Gear High Performance Gear Set For Dana 30 JK Short Reverse Pinion / 4.56 |
| Type | Final Drive Gears |
| Condition | New |
| Ships | Same business day (in stock), from the USA |
| Warranty | 1-year |
Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
It works well for many JKs on 35s, especially two-doors and manual-transmission Jeeps. Heavier four-door automatics that carry gear or tow often step down to 4.88.
No. The Rubicon uses a Dana 44 front. This set is for the reverse-rotation Dana 30 front on non-Rubicon JK models.
Yes if the Jeep came with 3.73 gears. A 3.21-geared Jeep has the smaller carrier series and needs a 3.73-and-up carrier or a locker to mount a 4.56 ring gear.
Yes. Both axles must have the same ratio. Running different ratios front and rear will bind the driveline in four-wheel drive and can damage the transfer case.
Yes. Update the tire size and axle ratio with a programmer or dealer tool so the speedometer, transmission shifting and stability control use the new gearing.
